A globally continuous state-space representation of switched networks

The state variable approach is a numerically efficient and analytically meaningful method of predicting and characterizing the transient responses of power-electronic-based systems. An automated method of establishing state-space models of switched electrical networks is considered. In this modeling approach, the minimal state-space representation of the overall system is generated dynamically as each topology is encountered. Due to the changing topology, the simulation of a switched circuit requires concatenation of the solutions of initial value problems (IVPs) corresponding to time intervals between switching events. In this paper, a transformation of state variables is derived such that the computer-generated equations have the same dimension and the new states are continuous throughout the study. This feature eliminates the need for re-initializing the ODE solver and sets the stage for automated state-space averaging and system-level analysis of switched circuits. The algorithm is verified using a practical example of a synchronous machine-rectifier system.